* qatar/master: (47 commits) lavc: hide private symbols. lavc: deprecate img_get_alpha_info(). lavc: use avpriv_ prefix for ff_toupper4. lavc: use avpriv_ prefix for ff_copy_bits and align_put_bits. lavc: use avpriv_ prefix for ff_ac3_parse_header. lavc: use avpriv_ prefix for ff_frame_rate_tab. lavc: rename ff_find_start_code to avpriv_mpv_find_start_code lavc: use avpriv_ prefix for ff_split_xiph_headers. lavc: use avpriv_ prefix for ff_dirac_parse_sequence_header. lavc: use avpriv_ prefix for some dv symbols used in lavf. lavc: use avpriv_ prefix for some flac symbols used in lavf. lavc: use avpriv_ prefix for some mpeg4audio symbols used in lavf. lavc: use avpriv_ prefix for some mpegaudio symbols used in lavf. lavc: use avpriv_ prefix for ff_aac_parse_header(). lavf: hide private symbols. lavf: use avpriv_ prefix for some dv functions. lavf: use avpriv_ prefix for ff_new_chapter(). avcodec: add CODEC_CAP_DELAY note to avcodec_decode_audio3() documentation avcodec: clarify the CODEC_CAP_DELAY note in avcodec_decode_video2() avcodec: clarify documentation of CODEC_CAP_DELAY ... Conflicts: configure doc/general.texi libavcodec/Makefile libavcodec/aacdec.c libavcodec/allcodecs.c libavcodec/avcodec.h libavcodec/dv.c libavcodec/dvdata.c libavcodec/dvdata.h libavcodec/libspeexenc.c libavcodec/mpegvideo.c libavcodec/version.h libavformat/avidec.c libavformat/dv.c libavformat/dv.h libavformat/flvenc.c libavformat/mov.c libavformat/mp3enc.c libavformat/oggparsespeex.c Merged-by: Michael Niedermayer <michaelni@gmx.at>
		
			
				
	
	
		
			71 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			71 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * Audio and Video frame extraction
 | |
|  * Copyright (c) 2003 Fabrice Bellard
 | |
|  * Copyright (c) 2003 Michael Niedermayer
 | |
|  * Copyright (c) 2009 Alex Converse
 | |
|  *
 | |
|  * This file is part of FFmpeg.
 | |
|  *
 | |
|  * FFmpeg is free software; you can redistribute it and/or
 | |
|  * modify it under the terms of the GNU Lesser General Public
 | |
|  * License as published by the Free Software Foundation; either
 | |
|  * version 2.1 of the License, or (at your option) any later version.
 | |
|  *
 | |
|  * FFmpeg is distributed in the hope that it will be useful,
 | |
|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 | |
|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | |
|  * Lesser General Public License for more details.
 | |
|  *
 | |
|  * You should have received a copy of the GNU Lesser General Public
 | |
|  * License along with FFmpeg; if not, write to the Free Software
 | |
|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 | |
|  */
 | |
| 
 | |
| #include "aac_ac3_parser.h"
 | |
| #include "aacadtsdec.h"
 | |
| #include "get_bits.h"
 | |
| #include "mpeg4audio.h"
 | |
| 
 | |
| int avpriv_aac_parse_header(GetBitContext *gbc, AACADTSHeaderInfo *hdr)
 | |
| {
 | |
|     int size, rdb, ch, sr;
 | |
|     int aot, crc_abs;
 | |
| 
 | |
|     if(get_bits(gbc, 12) != 0xfff)
 | |
|         return AAC_AC3_PARSE_ERROR_SYNC;
 | |
| 
 | |
|     skip_bits1(gbc);             /* id */
 | |
|     skip_bits(gbc, 2);           /* layer */
 | |
|     crc_abs = get_bits1(gbc);    /* protection_absent */
 | |
|     aot     = get_bits(gbc, 2);  /* profile_objecttype */
 | |
|     sr      = get_bits(gbc, 4);  /* sample_frequency_index */
 | |
|     if(!avpriv_mpeg4audio_sample_rates[sr])
 | |
|         return AAC_AC3_PARSE_ERROR_SAMPLE_RATE;
 | |
|     skip_bits1(gbc);             /* private_bit */
 | |
|     ch      = get_bits(gbc, 3);  /* channel_configuration */
 | |
| 
 | |
|     skip_bits1(gbc);             /* original/copy */
 | |
|     skip_bits1(gbc);             /* home */
 | |
| 
 | |
|     /* adts_variable_header */
 | |
|     skip_bits1(gbc);             /* copyright_identification_bit */
 | |
|     skip_bits1(gbc);             /* copyright_identification_start */
 | |
|     size    = get_bits(gbc, 13); /* aac_frame_length */
 | |
|     if(size < AAC_ADTS_HEADER_SIZE)
 | |
|         return AAC_AC3_PARSE_ERROR_FRAME_SIZE;
 | |
| 
 | |
|     skip_bits(gbc, 11);          /* adts_buffer_fullness */
 | |
|     rdb = get_bits(gbc, 2);      /* number_of_raw_data_blocks_in_frame */
 | |
| 
 | |
|     hdr->object_type    = aot + 1;
 | |
|     hdr->chan_config    = ch;
 | |
|     hdr->crc_absent     = crc_abs;
 | |
|     hdr->num_aac_frames = rdb + 1;
 | |
|     hdr->sampling_index = sr;
 | |
|     hdr->sample_rate    = avpriv_mpeg4audio_sample_rates[sr];
 | |
|     hdr->samples        = (rdb + 1) * 1024;
 | |
|     hdr->bit_rate       = size * 8 * hdr->sample_rate / hdr->samples;
 | |
| 
 | |
|     return size;
 | |
| }
 |